Synopsis The pilot and passenger departed on a local flight, planned to last one hour. After the aircraft became airborne, it gained altitude momentarily; the pitch angle was then seen to decrease, and the aircraft descended to a height of approximately ten feet above the runway surface. The pitch angle increased again and the aircraft climbed to a height variably described as up to 200 feet above ground level before entering a gentle turn to the left. The angle of bank then abruptly increased, the nose pitched down sharply, and the aircraft descended to the ground in a steep, nose-down, left-wing-low attitude. The pilot was fatally injured, and the passenger received serious injuries. Other Factual Information The pilot was certified and qualified to conduct the flight in accordance with existing regulations. It could not be determined when the pilot had last practised, or received instruction pertaining to, precautionary and forced approach procedures or stall recognition, avoidance, and recovery. There is no regulatory requirement for recurrent training or examination subsequent to pilot licensing. There is no evidence that incapacitation or physiological factors affected the pilot's performance. On 10 June 1996, an instructor and student were flying the occurrence aircraft on a training flight. They reported that while they were in level, cruise flight, the aircraft engine (Continental O-200-A) was running rough and it lost approximately 200 rpm. They returned to the Peterborough airport for an uneventful landing. The aircraft was taken to a maintenance facility and the defect was verbally reported. Maintenance personnel subsequently diagnosed that the carburettor was the source of the problem. They replaced the carburettor, tested the engine, and returned the aircraft to service on 21 June 1996. Because many starts of the engine were conducted while troubleshooting the rough running, the starter clutch began to slip, and the engine starter drive unit was also changed on 21 June. After the starter drive unit was changed, neither the engine oil nor the oil screen was checked for contamination, nor is there any manufacturer or regulatory requirement for the check to be carried out. The occurrence flight was the first since the aircraft was returned to service. At the accident site, the engine tachometer indicated approximately 2,100 rpm. The TSB's analysis of the instrument revealed that the pointer was captured during the impact sequence by the broken face glass, indicating that the engine was rotating at a minimum of 2,130 rpm. One witness to the accident indicated that, from the time the aircraft began its take-off roll, the engine sounded as though it was not operating smoothly. The Cessna Pilot's Operating Handbook states that Any sign of rough engine operation or sluggish engine acceleration is good cause for discontinuing the takeoff. No discrepancies were noted with the airframe, airframe systems, or propeller that would have contributed to the accident. Impact witness marks indicated that the ailerons were deflected in a full right-turn command position. The position of the elevators and rudder at impact could not be determined. During the field examination of the aircraft, a substantial amount of ferrous material was discovered in the engine oil and engine oil screen. Accordingly, the engine was removed and taken to the TSB Engineering Branch for detailed examination. It was determined that the composition of the ferrous material was consistent with that of bearing material. The starter drive unit which had been removed on 21 June 1996 was examined. It was determined that the needle bearings in the starter drive gear assembly had failed prior to its removal and that wear ensued between the wheel stub shaft and the starter drive clutch gear. This wear produced metal contamination which was carried throughout the engine by the lubricating oil. Further examination of the engine revealed that some of these wear particles from the starter drive unit that was removed on 21 June had become lodged in the hydraulic lifters and rendered four of the eight lifters inoperative. Information from the engine manufacturer indicated that four inoperative lifters on two cylinders may reduce the engine power output by as much as 30 per cent. The runway at Peterborough Airport was undergoing resurfacing at the time of the occurrence and a portion of it was closed. The take-off run available was 2,400 feet for aircraft operations. Ten degrees of flaps were extended for the take-off. Performance calculations for the aircraft operating at maximum gross weight, with ten degrees of flap extended, showed that, on the day of the occurrence, the aircraft would have required a ground roll of 811 feet, and in excess of 1,524 feet to climb to 50 feet above ground level. The estimated aircraft take-off weight was 1,619 pounds. The certificated maximum take-off weight is 1,600 pounds.